Automobile radio antenna



Nov. 4, 1958 J. ROSENBAUM 2,859,441

AUTOMOBILE RADIO ANTENNA Filed June 21, 1957 INVENTOR. Jacob K058054007 zz'razzriy United States Patent Ll AUTOMOBILE RADIO ANTENNA Jacob Rosenbaum, Spring Valley, N. Y.

Application June 21, 1957, Serial No. 667,104

4 Claims. (Cl. 343-712) The present invention relates to automobile antennas.

Many efforts have been made to provide an effective automobile antenna free of faults. The common extensible rod antenna is subject to breakage, has a high impedance, is positioned close to the source of ignition interference, and is conspicuous. Other antennas for automobiles have a low effective height, or may pick up a large amount of ignition noise, or are difficult to mount and maintain in good operating condition.

It is an object of the present invention to provide a sturdy, effective, low impedance antenna which is inconspicuous and has a low sensitivity to ignition noise.

Another object of the invention is to provide an automobile antenna which has no propecting parts subject to breakage.

Another object is to provide an antenna having a high immunity to short-circuiting under inclement weather conditions, by virtue of its low impedance.

The objects of the invention are achieved by using as the antenna a separable or distinct large metallic portion of the body of an automobile which may be readily insulated from the rest of the body. More particularly, the lid or cover of the trunk, which is usually in the rear, but in some automobiles is at the front, is completely insulated from the body and provided with a connection, such as a coaxial cable, to the radio receiver. Thus, a low impedance, practically-indestructible antenna having a large area is provided far removed from the sources of interference of the automobile.

Other objects and advantages of the invention will become apparent and the invention will be fully understood from the following description and the drawing in which:

Fig. 1 is a rear View of an automobile.

Fig. 2 is a side view showing portions in cross sec tions.

Referring to the drawing, the automobile has a body provided with a trunk which in some automobiles is at the front but in most cases is at the rear as here shown. The entire trunk lid 11 is insulated from the body 10 preferably by flexible insulation 15 which extends round the sides 16 and top 17 of the lid. The insulation 15 is fastened in a channel 18 which extends along the sides and top of the lid. Along the bottom of the lid there is an internal flange 19 adapted to rest on insulation 20 mounted in a channel 21.

The lid 11 is provided with a handle and or lock adapted to operate with a latch 26, which engages a keeper plate 27. The keeper plate is mounted through insulation 28 on a bracket 29 fixed to the body of the automobile by insulated screws or other suitable means, not shown.

The upper portion of lid 11 is connected by one or more hinges 30 to the body 10. Each hinge includes an arm 31 fastened to the body 10 through a plate of insulation 32 and an arm 33 fastened to the lid 11 through insulation 35. Arms 31 and 33 may be fastened to the body and the trunk lid by insulated screws or other suitable means. Thus the entire trunk lid is insulated from the body of the automobile.

A suitable conductor 40, which may be a coaxial cable, is conductively connected to the lid and extends to the antenna terminal of the radio receiver. The outer conductor of the coaxial cable is preferably grounded at one or more points therealong, while the inner conductor, of course, forms the connection between the antenna and the radio receiver. By virtue of the fact that the antenna has a low impedance, a small antenna coupling coil may be used in the radio receiver with a consequent saving of expense.

The relatively great distance of the antenna from the electrical noise producing sources in the automobile, such as the spark plugs, distributor, generator, ignition coil, etc. enables the antenna to have a high signal to noise ratio.

It Will be evident that the antenna disclosed herein may be used for a transmitter as Well as a receiver. For the sake of simplicity l have shown only one embodiment of my invention but it will be evident to those skilled in the art that many variations and modifications can be made without departing from the principles of my invention. The invention, therefore, is not to be construed as limited except as defined in the following claims.

I claim:

1. In combination with an automobile having a body including a trunk, an antenna comprising: a metallic lid for said trunk, latching means and hinge means mechanically connecting the lid to the automobile body, means for completely insulating said trunk lid from the body, said means for insulating said trunk lid including insulating means in the latching means and hinge means, and a lead wire connected to the trunk lid.

2. An antenna for an automobile having an internal combustion engine at the front thereof, a metallic body and a rear trunk, said antenna comprising, a metallic lid for said trunk, hinge means for connecting the lid to the body, means for fastening the hinge means to the lid and the body, said fastening means including means for insulating the lid from the body, insulating means round the periphery of the trunk lid and between the lid and the body for insulating the lid from the body, and a lead wire connected to the trunk lid.

3. An antenna according to claim 2, wherein said trunk lid includes latching means and means for insulating said latching means from the body of the automobile.

4. An antenna for an automobile having a metallic body, an engine near one end and a trunk near the other end, said antenna comprising a metallic lid for said trunk, hinge means for connecting the lid to the body, means for fastening the hinge means to the lid and the body, said fastening means including means for insulating the lid from the body, insulating means inside said trunk lid round the periphery of the trunk lid and between the lid and the body for insulating the lid from the body, means for latching the trunk lid to the body, said latching means including a keeper plate insulatingly mounted on said body, and a high frequency conductor connected to the inside of the trunk lid.

References Cited in the file of this patent UNITED STATES PATENTS 2,351,947 Gabler June 20, 1944 2,575,471 Schweiss et al. Nov. 20, 1951 FOREIGN PATENTS 366,421 Italy Dec. 27, 1938 

